Store Twenty One, an affordable fashion chain, is due to welcome its first customers in the weeks leading up to Christmas, with a final date yet to be announced.
The prominent premises is in a prime location in the Square and was occupied by the now defunct Woolworth's chain, which had to leave after the company revealed it was shutting all of its stores this time last year.
"It is fantastic that in these difficult financial times we have a business opening in the market square," said Town Centre Operations Manager Richard Blagg.
"If all goes well, it should be opening in about two weeks' time," he added.
Part of the QS Group, the Retford branch of Store Twenty One will be one of around 50 such outlets dotted across the country.
No one from QS Group was available for comment.
Retford Woolworth's officially closed in early January with the loss of 28 jobs. The building has been vacant since then.